Csn1 and Csn2 affect heterochromatin integrity independently of RNAi. (A) cen1:ade6+ silencing assay. Equivalent cell numbers of the indicated strains were spotted in serial dilutions on non-selective plates (N/S), or plates containing 10ug/ml adenine (LOW ADE) or no adenine (-ADE). (B) Assay for silencing at the silent mating-type locus (mat3-M:ura4+). Plates are non-selective (N/S), lacking uracil (-URA) or supplemented with FOA (+FOA). (C) ChIP analysis of H3K9me2 levels at centromeric outer repeats (cen-dg) or the silent mating-type locus (mat) relative to act1+, normalised to wild-type. (D) Northern analysis of pericentromeric siRNAs. snoRNA58 (snR58) is a loading control.